c# - 正在保存图像，GDI+ 中出现一般性错误

Question

我得到一个

A generic error occurred in GDI+

当我调用 img.Save(path, jpegCodec, encoderParams);
时出现异常这是所有代码:

    private Image img;

    private void button1_Click(object sender, EventArgs e)
    {
        this.img = Image.FromFile(@"path");

        pictureBox1.Image = img;

        if (img.Height < pictureBox1.Height && img.Width < pictureBox1.Width)
        {
            this.pictureBox1.SizeMode = PictureBoxSizeMode.CenterImage;
        }

        Graphics g = Graphics.FromImage(img);

        Font font=new Font("Arial",16);

        SolidBrush brush = new SolidBrush(Color.Black);

        brush.Color = Color.FromArgb(255, 0, 0, 255);

        g.DrawString("myName", font, brush, img.Width - 178, img.Height-105);
    }

    private void button2_Click(object sender, EventArgs e)
    {
        Bitmap bitmap = new Bitmap(img);

        saveJpeg(@"path", bitmap, 85L);
    }

    private void saveJpeg(string path, Bitmap img, long quality)
    {
        // Encoder parameter for image quality
        EncoderParameter qualityParam =new EncoderParameter(Encoder.Quality, quality);

        // Jpeg image codec
        ImageCodecInfo jpegCodec = getEncoderInfo("image/jpeg");

        if (jpegCodec == null)
            return;

        EncoderParameters encoderParams = new EncoderParameters(1);
        encoderParams.Param[0] = qualityParam;

        //img.Save(path, jpegCodec, encoderParams);
        img.Save(path, jpegCodec, encoderParams);
    }
    private ImageCodecInfo getEncoderInfo(string mimeType)
    {
        // Get image codecs for all image formats
        ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders();

        // Find the correct image codec
        for (int i = 0; i < codecs.Length; i++)
            if (codecs[i].MimeType == mimeType)
                return codecs[i];
        return null;
    }

你愿意帮我吗？

Answer 1

只要通过从文件加载图像创建的图像对象存在，该文件就在使用中。文件正在使用时，您无法使用相同名称保存图像。

不是使用 Image.FromFile 加载图像，而是打开文件流并使用 Image.FromStream 创建图像，然后关闭文件流。这样文件就不再使用了，您可以替换它。